The graph shows the combination of swells directed at Los Lances over a normal northern hemisphere summer, based on 5070 NWW3 model predictions since 2006 (values every 3 hours). The wave model does not forecast wind or surf right at the shore so we have chosen the optimum grid node based on what we know about Los Lances. In the case of Los Lances, the best grid node is 34 km away (21 miles).

The rose diagram illustrates the distribution of swell sizes and directions, while the graph at the bottom shows the same thing but lacks direction information. Five colours illustrate increasing wave sizes. Blue shows the smallest swells, less that 0.5m (1.5 feet) high. These occurred only 89% of the time. Green and yellow show increasing swell sizes and red illustrates the biggest swells, greater than >3m (>10ft). In each graph, the area of any colour is proportional to how commonly that size swell was forecast.

The diagram implies that the most common swell direction, shown by the biggest spokes, was W, whereas the the prevailing wind blows from the NW. Because the wave model grid is offshore, sometimes a strong offshore wind blows largest waves away from Los Lances and away from the coast. We lump these in with the no surf category of the bar chart. To avoid confusion we don't show these in the rose plot. Because wind determines whether or not waves are surfable at Los Lances, you can select a similar diagram that shows only the swells that were expected to coincide with glassy or offshore wind conditions. During a typical northern hemisphere summer, swells large enough to cause good for surfing waves at Los Lances run for about 11% of the time.

IMPORTANT: Beta version feature! Swell heights are open water values from NWW3. There is no attempt to model near-shore effects. Coastal wave heights will generally be less, especially if the break does not have unobstructed exposure to the open ocean.